Can I still use express-validator even if there is no concept of email?

Question

So I am developing a signup route handler in Express with TypeScript. I am using express-validators to avoid all this code I had to write out in my route handler, but in the documentation that I quickly scanned through, I do not see an example for username, only for email. Anyone with more experience know if I can get away with just implementing validation for just password and passwordConfirmation and just hard code validation for username?

This is what I have thus far:

import express, { Request, Response } from "express";
import { body } from "express-validator";

const router = express.Router();

router.post(
  "/auth/signup",
  [
    body("password")
      .trim()
      .isLength({ min: 4, max: 20 })
      .withMessage("Must be between 4 and 20 characters"),
    body("passwordConfirmation").custom((value, { req }) => {
      if (value !== req.body.password) {
        throw new Error("Passwords must match");
      }
    }),
  ],
  (req: Request, res: Response) => {
    const { username, password, passwordConfirmation } = req.body;

    // const existingUser = await usersRepo.getOneBy({ username });
    // if (existingUser) {
    //   return res.status(422).send({ username: "Username already in use" });
    // }

    // const user = await usersRepo.create({
    //   username,
    //   password,
    //   passwordConfirmation,
    // });

    // req.session.userId = user.id;

    // res.status(200).send({ username: req.body.username });
  }
);

export { router as signupRouter };

Of course I am aware I am missing async in front of the callback to use what is commented out.

Would what I have commented out work in the same environment as express-validators?

Answer 1

You can validate either username and email using oneOf and by passing validationChains. Check the document with an example here

Go through this example for more clarification

    const validation = [
    oneOf([
    check('useroremail')
    .exists()
    .withMessage('username is required')
    .isLength({ min: 3 })
    .withMessage('wrong username length'),
    check('useroremail')
    .exists()
    .withMessage('Email is required')
    .isEmail()
    .withMessage('Email is not valid'),
    ]),
    check('password')
    .exists()
    .withMessage('password is required')
    ];
    function ValidationErrors(req, res, next) {
    const errors = validationResult(req);
    if (!errors.isEmpty()) {
    console.log(util.inspect(errors.array()));
    return res.status(422).json({ errors: errors.array() });
    }
    next();
    };
    router
    .post('/', validation, ValidationErrors,
    (req, res) => 
    {
    const isEmail = validator.isEmail(req.body.useroremail);
    res.status(200).json({ isEmail });
    });